Prof. Meenakshi Rao's Class Explores Chemistry in Daily Life

June 06, 2013

When members of the chemistry department asked Meenakshi Rao if she’d develop a new introductory seminar course on a subject close to her heart for the fall 2013 semester, she jumped at the chance. Rao, Barnard’s senior lecturer in chemistry and director of the organic chemistry labs, has taught at the College for 22 years and knew exactly how to draw new students to the field: a course on forensics and chemistry in everyday life.

One of her inspirations for the course, “From Pumpkin Pie to CSI,” the latter referring to the popular television show, came from a trip Rao took with a group of students recently to the “CSI: The Experience” exhibition at the Discovery Times Square museum. The students solved hypothetical crimes by examining blood types and matching DNA samples to potential suspects. They were fascinated by the experience, and the memory of their enthusiasm has stayed with Rao ever since. She still keeps pictures from the trip on a bulletin board outside her office. “The excitement in their expressions was incredible,” she says.

It doesn’t hurt that Rao is also a fan of Sherlock Holmes. Her appetite for mysteries fuels her own passion for studying forensics. “Sherlock Holmes, CSI, The Mentalist—I can’t get enough of it,” she admits with a laugh, noting that it’s the way that crime stories hinge on the science—the analysis of a hair fiber or a tooth filling—that captivates her. She’s not alone: Today’s students have grown up watching images of scientists working in labs, using chemistry to solve crimes in ubiquitous crime procedurals such as CSI. New technology in forensics has also brought increased media attention to the field as investigators have solved cold cases and reversed past convictions with new DNA evidence. “When I was growing up, I wasn’t exposed to these topics,” Rao says. “You didn’t see science in the mainstream media.” Her own undergraduate and master’s education at India’s Bangalore University rarely covered how chemistry could be found in the outside world.

Forensics and a Calendar of Chemistry

That won’t be the case for Rao’s students. In the weeks the course is devoted to forensics, students will learn crime-scene chemistry and evidence-analysis techniques. For example, they’ll learn how they can use atomic absorption spectroscopy, a way to detect trace amounts of elements in a sample, to identify the additional metals in a gold tooth filling found at a crime scene. Knowing the filling’s makeup can lead investigators back to a specific dentist who uses a particular filling mixture—and to a list of patients who could be potential suspects.

Students who continue in chemistry will encounter atomic absorption spectroscopy in the course “Quantitative and Instrumental Techniques,” where the method is used to determine how trace elements found in certain foods match the foods’ dietary information. An early understanding of how scientists use these techniques in fields such as forensics gives students a broader sense of how hard science is applied outside the classroom or lab.

The changing seasons and holidays also inspired Rao to design “Calendar of Chemistry.” As the leaves change, she will teach the chemistry of color and invite her students to her family’s home on Long Island. The trip, which includes a hike through the fall foliage, has become an annual tradition for Rao and the students in her fall courses. Rao will then teach the chemistry of fear to coincide with Halloween, exploring how our bodies produce chemicals that induce a fight-or-flight response after a sudden fright.

Popular cooking shows have also introduced food chemistry to a mainstream audience; before Thanksgiving break, Rao will delve into that topic. Students will learn how one small structural difference in the otherwise identical molecular formulas of nutmeg and cloves—common pumpkin pie ingredients— makes these two spices dramatically different in aroma and taste. She will devote the final class to the chemistry of ice as students depart for winter break. Rao will also have her students explore chemistry in art restoration, forgery detection, cosmetics, even the chemistry of love.

Putting Science in Context

Rao designed the new course to provoke a passion for chemistry in first-year students—even before they take “General Chemistry I.” Telling the stories behind the science captures their attention, she explains. “Then they’re awake for the chemistry part of it.”

Her passion for chemistry and novel approaches to teaching it helped earn Rao Barnard’s Emily Gregory Award for excellence in teaching and for devotion and service last year. Her methods have adapted to changes in her students. Over the past decade, she has observed that many students want to apply their chemistry studies to careers outside the traditional pursuits of medicine, research, or academics; Rao sees some of her former students going into such fields as art restoration and forensics.

The students respond so well to stories of the real-world applications of science that she discusses chemistryrelated news articles in class. The more she exposes her first-year students to the ways science fits into life, the more likely they’ll find inspiration in the field. “If high-school students were exposed to these stories more, most would consider majoring in chemistry in college,” she believes. Rao expects a full classroom for the new seminar this fall, and hopes to add a lab component in coming years.